Phosphorous Nutrient Deficiency

Phosphorous Nutrient Deficiency of Sunflowers, Helianthus annuus

Ngoc Chau Tran

Cal State Fullerton

Abstract: The objective of this experiment was to determine whether or not a complete

nutrient solution would have increased stem width, height, and leaf length compared to 25%

phosphorous. My hypothesis was that sunflowers with a complete solution of nutrients would

have the same growth compared to sunflowers with 25% phosphorous deficiency. The

experiment was conducted by setting up two groups of sunflower seeds, control and

treatment. Each group contained five seeds. The nutrients were added when the seeds had

germinated. The controls were treated with a complete nutrient solution, whereas the

treatment was treated with 25% phosphorous deficiency. Both groups were watered regularly

with the nutrient solutions until harvest time. The measurements of both groups were taken

periodically. During harvest time, the healthiest plant in each pot was measured for stem

width (mm), height (cm), and leaf length (mm). The results indicated that there was no

significant change in the controls and treatments because the p-values of all three types

of measurements were greater than 0.05. Therefore, the null hypothesis was accepted.

Despite the insignificant results, observations and measurements of growth in both groups

of sunflowers in terms of stem widths, lengths, and leaf lengths suggested that the

presence or absence of phosphorous did influence the plant growths.

Phosphorous Nutrient Deficiency of Sunflowers, Helianthus annuus

Ngoc Chau Tran

Cal State Fullerton

Abstract: The objective of this experiment was to determine whether or not a complete

nutrient solution would have increased stem width, height, and leaf length compared to 25%

phosphorous. My hypothesis was that sunflowers with a complete solution of nutrients would

have the same growth compared to sunflowers with 25% phosphorous deficiency. The

experiment was conducted by setting up two groups of sunflower seeds, control and

treatment. Each group contained five seeds. The nutrients were added when the seeds had

germinated. The controls were treated with a complete nutrient solution, whereas the

treatment was treated with 25% phosphorous deficiency. Both groups were watered regularly

with the nutrient solutions until harvest time. The measurements of both groups were taken

periodically. During harvest time, the healthiest plant in each pot was measured for stem

width (mm), height (cm), and leaf length (mm). The results indicated that there was no

significant change in the controls and treatments because the p-values of all three types

of measurements were greater than 0.05. Therefore, the null hypothesis was accepted.

Despite the insignificant results, observations and measurements of growth in both groups

of sunflowers in terms of stem widths, lengths, and leaf lengths suggested that the

presence or absence of phosphorous did influence the plant growths.

Introduction: The objective of this experiment was to determine the effects of nutrient

deficiency in sunflower, H. annuus. My null hypothesis was that sunflower plants that were

treated with a complete nutrient solution would be the same as plants that were 25%

deficient in phosphorous. My alternate hypothesis was that sunflower plants with a

complete nutrient treatment would have increased growth compared to plants with

phosphorous deficiency with respect to stem height, width, and leaf length. Phosphorous is

an essential nutrient for root formation, flowering, fruiting and ripening (Gayle et al.

2001). Ten elements that are required for normal growth in plants are carbon, hydrogen,

oxygen, potassium, calcium, magnesium, nitrogen, phosphorus, sulfur, and iron. The absence

of any one of these elements causes plants to display characteristic abnormalities of

growth known as deficiency symptoms. Often such plants do not reproduce normally (Raven et

al. 1999). One reason why phosphorous is essential in plants is because it is responsible

for the general health and vigor of all plants. Some specific growth factors that have

been associated with phosphorus are: stimulated root development, increased stalk and stem

strength, improved flower formation and seed production, more uniform and earlier crop

maturity, increased nitrogen N-fixing capacity of legumes, improvements in crop quality,

and increased resistance to plant diseases (Webb 2002). One reason why sunflowers were

chosen in the experiment was because sunflowers are easy to grow, the only single flower

that grows as high as three meters at a rate of about 30 centimeters a week, and are

really the most beautiful flowers in the world (Webb 2002). A study of nutrient deficiency

was done by a group of two scientists to determine the effect on dwarf sunflowers.

Materials and Method: The sunflower deficiency experiments began on February 19, 2002 in

the Cal State Fullerton green house and were harvested on May 3, 2002. Two groups of

plants were made, the control and treatment. Each group contained five sunflower seeds. A

complete nutrient solution of Ca(NO3)2, KNO3, KH2P04, MgSO4, Fe, and Micros was used in

the control group to compare the differences with the treatment plants that were

twenty-five percent phosphorus deficiency. Both groups were watered regularly (every 2

days) and the nutrient solutions were made four times throughout the experiment. The table

below showed how the control and treatment solutions were done. The plants were checked

periodically. Measurement of the longest leaf in (mm), stem in (mm), and height of each

plant in (cm) were inserted into the Mann Whitney test to obtain the p-value of the

nutrient deficiency experiment.

Table 1. Nutrient Experiment Deficiency of 25% phosphorous in Sunflower plants

Control Treatment of 25% phosphorous deficiency

Ca(NO3)2= KNO3=KH3PO4=MgSO4=Fe=Micros=Fill in half regular water in milk jar tank, and for

every liter of water of the other half of the tank, five milliliter of each nutrient was

added5 x 3.78 = 18.918.9 x 5 (number of nutrients) 18.9 = 113.4 a complete nutrient

solution Ca(NO3)2= KNO3=KH3PO4=MgSO4=Fe=Micros=P= 25%Fill in half regular water in

milk jar tank, and for every liter of water of the other half of the tank, five milliliter

of each nutrient was added excluding phosphorous.5 x 3.78 = 18.918.9 x 5= 94.9 (5 x 3.78

x .25%) = 99.26

Results: As a result of the experiment, my null hypothesis accepted. Sunflower plants that

were treated with a complete nutrient solution did not exhibit a significant increase in

growth compared to the 25% phosphorous nutrient deficiency plants. The mean and variance

in a complete solution for leaf lengths were 5.07 and 1.08 compared to 6.62 and 3.38 for

the 25% phosphorous deficiency (Figure 2); mean and variance in a complete solution for

stem widths were 0.35 and 0.01 compared to 0.33 and 0.01 for the 25% phosphorous

deficiency (Figure 1); mean and variance in complete solution for stem heights were 7.80

and 0.27 compared to 12.9 and 0.24 for the 25% phosphorous deficiency (Figure 3). It was

determined that there was not a significant change between a complete and 25% of

phosphorus nutrient deficiency solution because the p-values for stem width, height, and

leaf length were 0.44, 3.97, and 0.11 respectively, which were greater than 0.05.

Discussion: The results of the experiment showed that there was not a significant

difference between the two groups of sunflower plants, a complete solution group (control)

and, a 25% of phosphorous nutrient deficiency group (treatment), because the p-values of

solution Ca(NO3)2= KNO3=KH3PO4=MgSO4=Fe=Micros=P= 25%Fill in half regular water in

milk jar tank, and for every liter of water of the other half of the tank, five milliliter

of each nutrient was added excluding phosphorous.5 x 3.78 = 18.918.9 x 5= 94.9 (5 x 3.78

x .25%) = 99.26

Results: As a result of the experiment, my null hypothesis accepted. Sunflower plants that

were treated with a complete nutrient solution did not exhibit a significant increase in

growth compared to the 25% phosphorous nutrient deficiency plants. The mean and variance

in a complete solution for leaf lengths were 5.07 and 1.08 compared to 6.62 and 3.38 for

the 25% phosphorous deficiency (Figure 2); mean and variance in a complete solution for

stem widths were 0.35 and 0.01 compared to 0.33 and 0.01 for the 25% phosphorous

deficiency (Figure 1); mean and variance in complete solution for stem heights were 7.80

and 0.27 compared to 12.9 and 0.24 for the 25% phosphorous deficiency (Figure 3). It was

determined that there was not a significant change between a complete and 25% of

phosphorus nutrient deficiency solution because the p-values for stem width, height, and

leaf length were 0.44, 3.97, and 0.11 respectively, which were greater than 0.05.

Discussion: The results of the experiment showed that there was not a significant

difference between the two groups of sunflower plants, a complete solution group (control)

and, a 25% of phosphorous nutrient deficiency group (treatment), because the p-values of